Dry Mouth: Causes, Risks and What Helps

A dry mouth is easy to dismiss as an annoyance. It is worth taking more seriously than that, because saliva is doing far more work than you would guess, and losing it changes your risk of decay considerably.

The short answer

Saliva rinses food away, neutralises acid, carries minerals that repair early enamel damage, and controls bacteria. Without enough of it, decay accelerates, gums inflame more readily, breath worsens and dentures stop staying put. The commonest cause by a wide margin is medication, and most people never connect the two. Dry mouth is manageable, but it needs managing rather than tolerating.

What causes it

• Medication. Several hundred drugs reduce saliva, and the effect compounds when you take more than one. The usual suspects are antidepressants, antihistamines, blood pressure medicines, diuretics, inhalers, opioid painkillers and drugs for an overactive bladder. Never stop a prescribed medicine over this, but do mention it to us and to your GP, because alternatives sometimes exist.
• Simple dehydration. Not drinking enough, or losing more through exercise, alcohol or caffeine.
• Mouth breathing and snoring. Classically worst overnight and on waking. Often connected to a blocked nose or sleep apnoea.
• Medical conditions. Diabetes, particularly when poorly controlled, and Sjögren’s syndrome, an autoimmune condition that specifically targets the salivary and tear glands. Anxiety produces it too.
• Cancer treatment. Radiotherapy to the head and neck can permanently reduce saliva, and some chemotherapy does temporarily. Anyone in this group needs a much more intensive prevention regime, and we would want to see you more often.
• Smoking, vaping and alcohol, all of which dry the tissues directly.
• Age itself, less than people assume. Older people are more likely to be on drying medication, which is usually the real explanation.

Why it matters more than it feels like it does

The risk that concerns us most is decay, and specifically the speed of it. Without saliva doing the repair work, a mouth that has been stable for decades can develop several cavities in a year, often at the gumline and around the edges of existing fillings and crowns. It is one of the few situations where we would shorten your recall interval on the strength of one symptom.

Alongside that: more gum inflammation, more bad breath, oral thrush, a sore or burning tongue, cracked lips, difficulty tasting, and dentures that rub or will not stay in place because they rely on a film of saliva for suction.

What actually helps

• Sip water constantly and keep a bottle with you. Small and frequent beats a large glass occasionally.
• Sugar-free gum after meals. Chewing is the most effective way to stimulate what saliva you have. Anything containing xylitol is a good choice.
• Saliva substitutes. Gels, sprays and lozenges from the pharmacy, and a gel at night is the one most people find genuinely useful. Ask us or your pharmacist which suits you.
• High-fluoride toothpaste. This is the single most important protective step if your mouth is persistently dry, and it needs prescribing. Ask us about it.
• Spit, do not rinse, after brushing, so the fluoride stays on your teeth.
• Cut the frequency of sugar hard. With reduced saliva your teeth no longer have their normal recovery, so grazing is far more damaging than it was. See our guide to tooth decay.
• Avoid alcohol-based mouthwash, which will make it worse. Choose an alcohol-free one.
• Reduce caffeine and alcohol, and stop smoking or vaping if you can.
• Humidify the bedroom if it is worst overnight, and get a blocked nose looked at.

When to raise it with a doctor rather than us

See your GP if a dry mouth comes with dry, gritty eyes, joint pain or unusual fatigue, which together can suggest Sjögren’s syndrome. Also if you are unusually thirsty and passing more urine than normal, which needs diabetes ruling out, or if you notice swelling of the glands under your jaw or in front of your ears.

What it costs

A new patient examination is £89 including X-rays, £60 thereafter, and with dry mouth the X-rays matter because decay tends to start where you cannot see it. Hygiene appointments are £60 or £89 depending on length. Our dental plan from £15.95 a month makes more frequent visits considerably cheaper, which is relevant if you need to be seen three or four times a year rather than twice. Full list on the fees page.

Frequently asked questions

Can medication really cause this?

Yes, and it is the most likely explanation. Hundreds of common drugs list it, and taking two or three that each cause it mildly can add up to a genuinely dry mouth. Do not stop anything, but do tell your GP and pharmacist, because a switch is sometimes possible.

Will drinking more water fix it?

It helps and it is worth doing, but water does not replace saliva. It has no minerals to repair enamel and no antibacterial proteins. That is why the fluoride and sugar-frequency advice matters even if you are drinking plenty.

Why do my dentures keep coming loose?

Because upper dentures in particular rely on a thin film of saliva for suction. A dry mouth breaks that seal, which causes rubbing and slipping. Saliva gels help, and it is worth having the fit checked.

Is dry mouth permanent?

It depends on the cause. Dehydration, mouth breathing and medication effects are often reversible or improvable. Damage from head and neck radiotherapy, and Sjögren’s syndrome, tend to be permanent, in which case the focus shifts to protecting the teeth long term.

If your mouth has been dry for weeks rather than days, it is worth an appointment, mainly so we can get ahead of the decay risk. Call us on 01625 574609.

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